Defense Secretary Leon E. Panetta said Monday that service members who possibly were involved in the prostitution scandal in Colombia before the president’s visit last week have had their security clearances suspended.

Mr. Panetta spoke to reporters traveling with him on a plane en route to Colombia, where he is scheduled to meet with the Colombian defense minister in his first trip there as secretary of defense.

“My biggest concern is the issue of security and what could possibly have been jeopardized by virtue of this kind of behavior,” Mr. Panetta said.

Eleven military personnel are being investigated for their role in the scandal, but it’s not clear how many had security clearances.

“This trip is really trying to develop a key part of our new defense strategy, which is to develop and reinforce some very innovative partnerships in a very important region of the world that represents a key security interest for the United States,” he said.